Abstract: A method is provided for enhancing the shear stability of a high-viscosity fluid-water flow system, such as a core annular flow system. The method employs a family of demulsifier additives for maintaining separation of the fluids in biphasic flow. The additive family is sodium salts of polynuclear aromatic sulfonic acids. In one aspect, the high-viscosity fluid is heavy oil. A method to flow oil through a biphasic flow system is also provided. The method includes locating an oil in the biphasic flow system; placing water within the biphasic flow system; flowing the oil through the biphasic flow system within an annular flow of water; and subjecting the water in the biphasic flow system to a salt of a polynuclear aromatic sulfonic acid additive so as to improve shear stability of the oil and water.

Abstract: A method for determination for a given oil the relative stability of a water-in-oil emulsion that will be formed by that oil with water comprises measuring for the given oil the weight percent asphaltenes (A), total acid number (TAN), and ratio of the amount of naphthenic acids in the 450+ molecular weight to 450 molecular weight range (R); calculating an emulsion stability parameter, S=A+TAN*R; and determining whether the emulsion stability parameter, S, is greater than about 3; with a value above 3 being determinative of an emulsion more stable than one with a value less than 3.

Abstract: The invention is directed towards a chemical demulsifier formulation comprising an alkyl aromatic sulfonic acid additive with at least 16 carbon atom alkyl group and at least two 6 carbon-ring aromatic group and a co-additive selected from the group consisting of dipropylene monobutyl ether, aromatic naphtha, isoparaffinic solvent, cycloparaffinic solvent, aromatic solvent, diethylene glycol monobutyl ether, benzyl alcohol and mixtures thereof and a process for demulsification and desalting crude oil using the demulsifier formulation.

Abstract: The invention is directed towards a chemical demulsifier formulation comprising an alkyl aromatic sulfonic acid additive and a process for demulsification and desalting crude oil using the demulsifier formulation.

Abstract: The invention is directed towards a chemical demulsifier formulation comprising an alkyl aromatic sulfonic acid additive with at least 16 carbon atom alkyl group and at least two 6 carbon-ring aromatic group and a co-additive selected from the group consisting of dipropylene monobutyl ether, isoparaffinic solvent, cycloparaffinic solvent, diethylene glycol monobutyl ether, benzyl alcohol, and mixtures thereof.